Embodiments of the invention relate to managing Materialized Query Tables (MQTs) over fine-grained access control protected tables.
The issue of fine-grained access control has grown in importance to commercial and government users of relational databases, especially with recent government initiatives being put into place to strengthen overall security. Fine-grained access control may be used by an installation as part of a plan for complying with data protection laws such as the following:                Gramm-Leach Bliley Act        Health Insurance Portability and Accountability Act        European Union (EU) Data Protection Directive        Privacy laws in Canada, Japan, and Australia        Payment Card Industry Data Security Standards        Interagency Guidelines for Safeguarding Customer Information        Basel II operational controls, Sarbanes-Oxley internal controls        
Also, fine-grained access control may be used in response to high profile privacy breaches and identity theft cases and in response to customer and vendor pressure for increased privacy and security.
Materialized Query Tables (MQTs) are derived tables that are similar to views. However, MQTs pre-compute and store the contents of a view, rather than deriving the contents when the view is referenced in a Structured Query Language (SQL) statement. An MQT may be accessed directly like other tables by referencing the MQT in SQL statements. An MQT may also be accessed indirectly by a database query optimizer in order to optimize a SQL query against the same source tables as the MQT. The database optimizer determines that the data selected by the source query is a subset of the data in the MQT. The assumption is that a significant portion of the SQL query has been already pre-computed by the MQT and can be re-used to optimize the SQL statement.
However, there is a need in the art for improved application of fine-grained access control when using MQTs.